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Which is NOT a mechanism to make lipid-anchored membrane proteins?

A. C-terminal Prenylation
B. N-terminal Acylation
C. Covalently linking to glycosylphosphatidylinositol (GPI)
D. Protein phosphorylation

User Attersson
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Final answer:

The correct option is D. Protein phosphorylation does not create lipid-anchored membrane proteins. These proteins are anchored by mechanisms like C-terminal Prenylation, N-terminal Acylation, or linking to GPI - all involving covalent bonds with lipids.

Step-by-step explanation:

The option D. Protein phosphorylation is NOT a mechanism to create lipid-anchored membrane proteins. Lipid-anchored membrane proteins are anchored in the plasma membrane through covalent bonds with lipids. The three main mechanisms to achieve this are:

  • A. C-terminal Prenylation - The addition of a lipid group, such as a farnesyl group, to a cysteine residue of a protein, often occurring at the carboxyl terminus in a specific amino acid sequence known as the 'Caax' motif.
  • B. N-terminal Acylation - The attachment of a lipid group, such as myristic acid, to the N-terminus of a protein.
  • C. Covalently linking to glycosylphosphatidylinositol (GPI) - A post-translational modification where GPI is attached to the C-terminus of a protein, anchoring it to the membrane.

Conversely, protein phosphorylation, which is the addition of a phosphate group to an amino acid of a protein, does not serve to anchor proteins to membranes.

User Pomber
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